Preoperative oral caffeine as prophylaxis against post-spinal hypotension in patients undergoing orthopedic lower limb surgery: A randomized, placebo-controlled, double-blinded study.

BACKGROUND

This study aimed to investigate the efficacy of preoperative a caffeine tablet as prophylaxis against post-spinal hypotension in adult patients undergoing lower extremity orthopedic surgery.

METHODS

Patients aged 18-70 years who underwent lower limb orthopedic surgery were enrolled. In the caffeine group, the patient ingested a 200 mg caffeine tablet. In the control group, the patient ingested a placebo. The primary outcome was the number of patients with one or more hypotensive episodes within the first hour of spinal anesthesia, which was defined as a decrease in mean arterial pressure (MAP) <60 mmHg or a >20% decrease in MAP from baseline. The secondary outcomes were the number of patients who received ephedrine and the amount of ephedrine per patient within the first hour of spinal anesthesia.

RESULTS

80 patients were randomized to the caffeine group (n = 40) and control group (n = 40). One patient in the caffeine group was lost to follow-up. The number of patients with one or more hypotensive episodes within the first hour of spinal anesthesia was significantly lower (p = 0.013) in the caffeine group (n = 6, 15.3%) than in the control group (n = 17, 42.5%). The number of patients who received ephedrine as well as the amount of ephedrine per patient within the first hour of spinal anesthesia were significantly lower in the caffeine group than in the control group.

CONCLUSION

The preoperative ingestion of a 200 mg caffeine tablet could decrease the number of patients with hypotensive episodes and ephedrine requirements within the first hour of spinal anesthesia.

REGISTRATION: Pan African Clinical Trial Registry, registration number PACTR202311786558285, https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=26993.